He had a darkness that emitted light, for her. An emptiness that fulfilled her.
When he snorted drugs into his veins, when he drank till he puked, she disliked him. She loathed him, she wished he would die. But then she knew she would wish to die with him. And at nights, when he cried, she would hold him, rock him, and collect all the pieces of his being and try to make him whole again. 
A poisonous love. An inescapable love.

It was not that he did not try. He had tried rehab, a number of times, but in the end, he always relapsed. He had entered an abyss too deep to find a way out.

They did sometimes have happy days.When he was sober, they would go to the beach, find sea shells, talk, make love. She held tightly onto those fragile moments, for she knew they would not last long. His own tenebrosity would one day consume him. 

The day it did, the day he died of an overdose of drugs, she should have felt liberated, but she felt chained, to his soul, to his darkness that was for her, light. And she lived on, with the pain that was for her, love.